Re: [Evolution] Interaction with ProtonMail “Error syncing changes: mailbox 4 does not exist”

[Dan Kortschak <dan kortschak io>]

On Thu, 2020-05-28 at 09:26 +0200, Milan Crha via evolution-list wrote:
> On Wed, 2020-05-27 at 13:56 +0200, Dan Kortschak wrote:
> > [imapx:A] I/O: 'A00226 SELECT Spam'
> > [imapx:A] I/O: '* OK [UIDNEXT 14] Predicted next UID'
> > [imapx:A] I/O: '* OK [UIDVALIDITY 4] UIDs valid'
> > [imapx:A] I/O: '* FLAGS ()'
> > [imapx:A] I/O: '* OK [PERMANENTFLAGS (\Seen \SEEN \Flagged \FLAGGED
> > \Deleted \DELETED \Draft \DRAFT $junk junk nonjunk)] Flags
> > permitted.'
> > [imapx:A] I/O: '* 3 EXISTS'
> > [imapx:A] I/O: '* 0 RECENT'
> > [imapx:A] I/O: '* OK [UNSEEN 1] '
> > [imapx:A] I/O: 'A00226 OK [READ-WRITE] SELECT completed'
> > ...
> > [imapx:A] I/O: 'A00237 UID MOVE 3647 Spam'
> > [imapx:A] I/O: '* 3182 FETCH (FLAGS ($junk junk) UID 3647)'
> > [imapx:A] I/O: '* 3183 EXISTS'
> > [imapx:A] I/O: '* OK [UNSEEN 4] '
> > [imapx:A] I/O: 'A00237 NO Label does not exist'
>
>       Hi,
> the above shows that the 'Spam' folder can be selected, but one
> cannot
> move messages into it. Is it auto-populated by the server with the
> Junk
> flag? Maybe it is a server-side virtual folder.
>
> > [imapx:A] I/O: 'A00270 UID MOVE 13 Trash'
> > [imapx:A] I/O: '* 3 EXPUNGE'
> > [imapx:A] I/O: 'A00270 OK [COPYUID 4 13 453] COPY completed'
>
> This successfully moves a message to Trash folder on connect 'A'.
> Meanwhile had been made connection 'B' (and 'C').
>
> > [imapx:B] I/O: 'B00271 SELECT Trash'
> > [imapx:B] I/O: '* 3182 FETCH (FLAGS (\Seen nonjunk) UID 3647)'
> > [imapx:B] I/O: '* 3183 EXISTS'
> > [imapx:B] I/O: '* OK [UNSEEN 3] '
> > [imapx:B] I/O: '* OK [UNSEEN 0] '
> > [imapx:B] I/O: '* OK [UIDNEXT 454] Predicted next UID'
> > [imapx:B] I/O: '* OK [UIDVALIDITY 4] UIDs valid'
> > [imapx:B] I/O: '* FLAGS ()'
> > [imapx:B] I/O: '* OK [PERMANENTFLAGS (\Seen \SEEN \Flagged \FLAGGED
> > \Deleted \DELETED \Draft \DRAFT $junk junk nonjunk)] Flags
> > permitted.'
> > [imapx:B] I/O: '* 1 EXISTS'
> > [imapx:B] I/O: '* 0 RECENT'
> > [imapx:B] I/O: 'B00271 OK [READ-WRITE] SELECT completed'
>
> The connection 'B' has selected the Trash folder now.
>
> > [imapx:B] I/O: 'B00278 UID STORE 453 -FLAGS.SILENT (\DELETED)'
> > [imapx:B] I/O: 'B00278 OK UID STORE completed'
> > [imapx:B] I/O: 'B00280 UID STORE 453 -FLAGS.SILENT (JUNK)'
> > [imapx:B] I/O: 'B00280 NO mailbox 4 does not exist'
>
> IMAPx wants to unset \Deleted and Junk flags on the just moved
> message,
> because it's in the Trash folder, where the \Deleted flag doesn't
> make
> much sense. It succeeded with the \Deleted flag, but failed with the
> Junk flag.
>
> It seems to me that the server treats the Spam and Trash folders very
> specifically, the same as the Junk flag. Why it errors out this way
> might be a question for them.
>
> With respect of the real versus virtual Trash/Junk folders, unless
> the
> server forces subscription of these folders you can check "Show only
> subscribed folders" option in the account Properties->Receiving
> Options
> tab (which is unchecked by default), and it'll show you only
> subscribed
> folders. Which they are can be seen in Folder->Subscriptions for that
> account.
>
> I didn't get whether using virtual trash/junk behaves properly for
> the
> Trash/Spam sever-side folders or not. If it does weird things, then
> rather stay with the real folders. I'd definitely try to contact them
> and ask them about these errors. Feel free to use my text from above,
> which may or may not help them from the technical point of view.
>
> Maybe there are IMAP clients not showing these errors, but I'd be
> afraid that such clients just hide these errors from the user,
> pretending everything worked fine. Of course, I cannot tell for sure
> unless having similar communication log. There's always a chance that
> the IMAPx provide does something wrong.
>
>       Bye,
>       Milan
>
> P.S.: by the way, you can Reply to List (Ctrl+L in Evolution),
> instead
> of Reply to All, the same as I do here, which works better for me.

Thank you, Milan. This has been very helpful. I will forward the
information on to ProtonMail and hopefully they can use the it to
resolve the problem.

regards
Dan Kortschak